Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (leaves [119]-124).

Thesis (M.S.)--Michigan State University. Interdepartmental Physical Science, 2008. / Title from PDF t.p. (viewed on July 28, 2009) Includes bibliographical references (p.122-123). Also issued in print.

Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 69-79).

Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 209-221).

Thesis (Ph. D.)--University of Chicago, Dept. of Psychology, Committee on Human Development, August 1999. / Includes bibliographical references. Also available on the Internet.

Thesis (Ph.D.)--University of Delaware, 2009. / Principal faculty advisor: Elizabeth Higginbotham, Sociology. Includes bibliographical references.

<p>B lymphocytes are multifunctional and play important roles in both innate and adaptive immunity. The diverse roles of B cells can be attributed to the various and distinct types of B cells as determined by their origin, developmental stage, antigen specificity, and function.</p><p>Evidence suggests that human innate-like B cells (i.e., marginal zone and/or B1-like B cells) develop during fetal life. However, the characteristics of human fetal B-lineage cells are less understood. Recent studies of fetal and human umbilical cord B cells indicated that CD27, a well-established marker of human memory B cells, may also be expressed on human B1-like B cells. Indeed, CD27+ B cells are present in patients with hyper-IgM 1 (HIGM1) syndrome who are unable to generate GCs or memory B cells. In order to define the origin of naïve CD27+IgD+ human B cells, I studied B-cell development in both fetal and adult tissues.</p><p>In human fetal liver, most CD19+ cells co-express CD10, a marker of human developing B cells. Some CD19+CD10+ B cells express CD27, and these fetal CD27+ cells are present in the pro-B, pre-B, and immature/transitional B-cell compartments. Lower frequencies of phenotypically identical cells are also identified in adult bone marrow. CD27+ pro-B, pre-B, and immature/transitional B cells express recombination activating gene-1, terminal deoxynucleotidyl transferase, and Vpre-B mRNA comparable to their CD27− counterparts. CD27+ and CD27− developing B cells show similar immunoglobulin heavy chain gene usage with low levels of mutations, suggesting that CD27+ developing B cells are distinct from mutated memory B cells. Despite these similarities, CD27+ developing B cells differ from CD27− developing B cells by their increased expression of LIN28B, a transcription factor associated with the fetal lymphoid lineages of mice. Furthermore, CD27+ pro-B cells efficiently generate IgM+IgD+ immature/transitional B cells in vitro. Our observations suggest that CD27 expression during B-cell development identifies a physiologic state or lineage for human B-cell development distinct from the memory B-cell compartment.</p><p>Regarding B-cell repertoire, due to the random recombination of immunoglobulin V, D, and J gene segments during B-cell development, B cells are highly diversified in their antigen specificity. Through their specific B-cell antigen receptors (BCRs), B cells recognize foreign (and self-) antigens, and present these antigens to cognate T cells to elicit/establish humoral responses, such as germinal centers, immunological memory, and long-lasting circulating antibodies. Some bacteria and viruses escape the host’s immune system by mimicking host antigens, as B cells that recognize shared epitopes on self- and foreign antigens may provide protection against such pathogens; however, these B cells are normally eliminated by tolerance mechanisms during development. The extent of tolerization manifest among human B cells that recognize both self- and foreign antigens is unknown. Here, I and my colleagues use an efficient single B-cell culture method and multiplexed antigen-binding assays to determine the specificity of about 2,300 clonal IgG antibodies produced by the progeny of single transitional and mature B cells. We show that in healthy individuals, half of the self-reactive B cells crossreact with foreign antigen, and that the frequencies of crossreactive B cells decrease by half between the transitional and mature B-cell stages, indicating that a substantial fraction of foreign specificities is lost by the second tolerance mechanisms. In SLE patients, who show defective peripheral tolerance, frequencies of crossreactive B cells are unchanged between the B-cell stages. The crossreactive, mature B cells in SLE patients show distinct reactivity to foreign antigens. We propose that activating forbidden B cells may be a good strategy for protection against host-mimicking pathogens if we can control tolerance. </p><p>Activated B cells can present antigen to T cells, as well as differentiate into memory B cells and plasma cells. Indeed, activated B cells express high levels of MHCII and are considered to be professional antigen presenting cells (APC), along with dendritic cells and macrophages. APC can be used to discover the epitopes targeted in T-cell responses; T cells are co-cultured with autologous APC in the presence of antigens and T-cell responses are evaluated. With numerous epitope candidates, mapping T-cell epitopes requires large numbers of APC; the availability of APC in blood is a limiting component and leukapheresis is often required. Since B cells can be expanded in vitro more easily than other APC, they represent a solution for the challenge of isolating adequate numbers of APC from blood in order to determine T-cell antigen specificity. I modified our single B-cell culture to support efficient activation and proliferation of both naïve and memory human B cells for the purpose of generating large numbers of autologous APC. Briefly, naïve or memory B cells recovered from blood are cultured with recombinant human IL-2, IL-4, IL-21, and BAFF on CD154+ feeder cells; this culture supports extensive B-cell proliferation, with approximately 103 fold increases following 8 days in culture, and 106 fold increases when cultures are split and cultured for 8 more days. The capacity for continued proliferation is stable for at least another week. In culture, a significant fraction of naïve B cells undergo isotype switching and terminally differentiate into plasmacytes. Culture-derived (CD) B cells are readily cryopreserved, and when recovered, retain their ability to proliferate and differentiate. Significantly, proliferating CD B cells express high levels of MHCII, CD80, and CD86. I have examined the APC function of CD B cells and found that they present both allo- and microbial antigens to autologous T cells with comparable efficiency to PBMC. Moreover, I am able to activate and expand antigen-specific memory B cells; these cultured cells are highly effective in presenting antigen to T cells. This culture method provides a platform for studying the BCR and TCR repertoires within a single individual.</p> / Dissertation

Social media, an online arena for social behaviors such as self-presentation and social comparison, may have effects on users’ mood and mental health. Favorably presenting oneself is linked to positive outcomes such as higher self-esteem, whereas social comparison, in general and specifically upward social comparison to higher-performing others, is related to feelings of inadequacy, envy, and depression. Social comparison may explain the “Facebook depression effect,” acting as a mediator between time spent on social media and depressive symptoms. A correlational study is proposed that will ask 200 participants to report their time spent on various social media sites, self-presentation of themselves and their “friends,” social comparison orientation, and depressive symptoms. Expected findings are that time spent on social media and the degree of others’ perceived self-presentation will each be positively correlated with depression, and these relationships will be mediated by social comparison. This study will demonstrate that people feel depressed when they spend time on social media because they are frequently exposed to the self-enhancing images of others, which provides an opportunity for negative social comparison.

A presente pesquisa acompanha e analisa o desenvolvimento do projeto “________(título)” entre os anos 2012 e 2015. Este projeto consiste em um experimental de arquivamento , edição e apresentação de uma série de livros e instalações em espaços expositivos que contam com a participação de outros artistas. Na pesquisa, são abordadas questões como formação pessoal, performatividade e formas de apresentação e arquivamento em arte. Como resultado da pesquisa, será apresentada uma nova versão impressa do livro “________(título)” e uma experimentação expesitiva na Pinacoteca Barão de Ângelo do Instituto de Artes. / The present research monitors and analyzes the development of the project “________(title)” between the years 2012 and 2015. This project is an experimental process of archiving, editing and presentation of a serie of books and installations which include the participation of others artists. In the research are discussed issues like formation, performativity, forms of presentation and archiving in contemporary art. As result of the research are presented a new printed version of the “________(title)” book and the experimental installation at Pinacoteca Barão de Ângelo do Instituto de Artes.

In this study, I examine how congressional candidates present gendered identities on their campaign websites. In my theory of candidate gendered identity, drawn from literature on presentation of the self and gender performativity, I argue that candidates construct their personal identities in relation to universally understood archetypes, which stand for ideal representations of real-world characters or roles. Through an in-depth content analysis of the biographical pages of 2010 U.S. House of Representatives candidate campaign websites, I examine how candidates construct and perform a range of gender-based archetypal roles in various electoral contexts. Specifically, I look at how such factors as electoral context, candidate partisan identification, and incumbency status (or challenger status) determine the range of archetypal roles a candidate might choose to perform. What I find is that candidate gender matters, but only for some candidates in some contexts. For many candidates, these factors have an interacting effect on the manner in which a candidate presents his or her gender-based identity. This study contributes to our current understanding of how political candidates behave and present themselves in their political campaigns. In their efforts to connect with and gain the trust of potential voters, candidates present their personal identities through the performances of familiar archetypes with which those voters can easily identify.